Navy officials identified the deceased as Brett “Shady” Shadle, 31. Shadle had been a member of SEAL Team Six, the most elite of the SEAL teams and the one tasked with the historic May 2011 raid that killed al Qaeda leader Osama bin Laden.

Shadle was “one of the best,” a former colleague in the elite unit told ABC News.

“Both tactically on the battlefield and at home, he was one of the best SEALs I’ve ever worked with,” said an ex-SEAL Team Six member who served with Shadle for years. “His reputation was that of a great operator, a true friend and a nice guy.”

Shadle, a 31-year-old Pennsylvania native, was one of two SEAL Team Six members involved in a serious accident during routine freefall training in Arizona Thursday. Both SEALs were taken to a nearby hospital where Shadle succumbed to his injuries, according to officials. The other SEAL is in stable condition, the Navy said.

“[Shadle] should be remembered as a hero, a father, a friend and an American,” Shadle’s former SEAL colleague said. “He sacrificed everything for his country.”

The second SEAL, who was not identified, remained in stable condition according to the Navy press release. The accident is under further investigation.